Nanoparticle-based capillary electrochromatography

Abstract: In this work, lipid nanoparticles were used as pseudostationary phase, PSP, for protein separation in capillary electrochromatography, CEC. The aim of the work was to use a new analytical separation technique for future analysis of protein drugs by using lipid nanoparticles as a pseudo-stationary phase with conventional UV-detection. PSP-CEC was combined with UV-detection to study proteins elution. The tested proteins BSA, cytochrome c and insulin have been selected according to different hydrophobicities, sizes and isoelectric points (pI). A zwitter ionic buffer, MOPS, was used as an electrolyte at pH 7.4. The nanoparticles were tested for their compatibility with MALDI-TOF/MS (Matrix assisted laser desorption/ionization-time of flight). MADI-TOF/MS works with a suspension of lipid nanoparticles in MOPS that contains insulin and it can be a future possible detection method for PSP-CEC. All three proteins were successfully eluted with PSP-CEC combined with UV-detection. Nanoparticles coated with silver might be studied with “surface enhanced Raman spectroscopy”-detection.